Among its many intricacies and oddities, the English language yields several examples of word pairs that differ only by one letter between them and yet differ widely in meaning. One of the most common such pairings is complement and compliment. As close as they appear and, thus, as easy as they are to confuse, they have two entirely different definitions. To use one where you mean the other can be more embarrassing than you might imagine. One area where they’re easily mixed up is in descriptions of food and wine. To say, for example, that a certain burgundy complements the short ribs you’re serving for dinner is to mean that the flavor of one rounds out and brings out the flavor of the other; each completes the other. To substitute compliments for complements in such a situation isn’t entirely without justification. Still, a more apt use of compliment might be what you pay the host upon tasting the deliciously complementary flavors of the burgundy and short ribs. Typically, wines don’t dole out compliments.
Perhaps the trickiest pairing of this sort is affect and effect. Early on in school, you’re taught that the first of those is a verb, and the second is a noun. “Your sad eyes affect my mood” versus “Your sad eyes have an effect on my mood.” Although still easy enough to mix up, these verb-noun categories aren’t fixed! They’re subject to elaboration, which is to say that, in certain verbal situations, affect can also be a noun, and effect can also be a verb. The noun affect is etymologically linked to affection. It means “feeling or emotion.” The verb effect means “to bring about,” as in “The broken column effected the entire building’s collapse.” Oh, and just to complicate matters even more, the verb affect can also mean to “pretend”—as in an affectation—or “to like,” as in “If you affect that bouquet, I’ll buy it for you.” Clear?
Seriously, to switch around those two words would seem, at some point, inevitable and understandable. And some but-for-one-letter pairings challenge memory, sending you to the dictionary with every use—adverse or averse, immigrate or emigrate (okay, two letters’ difference there)?
But one instance in which getting a single letter wrong reflects badly on the writer is the university that goes by the name Johns Hopkins. People who say or write John Hopkins labor under the false impression that the institution is named after a man whose first name is, obviously, John. Those folks are only partly wrong, since Johns is indeed a first name, and a very unusual one. Johns Hopkins, a nineteenth-century Baltimore entrepreneur, abolitionist, and philanthropist, endowed the university and other institutions in the area that are named after him. Surely the 1800s saw other men named “Johns,” not “John,” but they didn’t leave a memorial legacy, and eventually the name became exclusively singular.